As a semiconductor device having a semiconductor thin film, an organic thin film device having an organic thin film composed of an organic semiconductor material attracts attention. In the manufacture of organic thin film devices, since an organic thin film may be formed easily by coating an organic semiconductor material, there is such an advantage that large area devices can be produced at a low cost.
Characteristics of an organic thin film device depend largely on a carrier transport property of the organic thin film. A higher carrier transport property enables the organic thin film device to exhibit excellent characteristics as an organic thin film device. For example, in the case of an organic field-effect transistor having a carrier transport layer composed of an organic thin film, a higher carrier transport property of the organic thin film enables more current to flow, and the adjustable amount of current can be broadened. As the result, excellent characteristics can be obtained as a transistor.
From this viewpoint, recently, organic semiconductor materials having high carrier transport properties are extensively examined. Examples of coatable organic semiconductor materials having high carrier transport properties include pentacene derivatives, polyalkylthiophene etc. However, a field-effect mobility (mobility) that is an indicator of carrier transport property of these organic semiconductor materials has not reached the level of mobility that is usually obtained for conventional amorphous silicon.
Accordingly, Patent Literature 1 proposes a chalcogen-containing polycyclic condensed-ring compound. It is shown that the compound is an organic semiconductor material that is soluble in various solvents and has a high field-effect mobility.